Reducing-valve.



PATBNTBD FEB. 24, 1903.

L. BRENNAN.

REDUGING VALVE.

APPLICATION FILED MAY 16, 1902.

x0 onsn.

UNITED STATES- [PATENT OFFICE. I

V LOUIS BRENNAN, OF GILLINGHAM, ENGLAND.

REDUCING-VALVE.

SPECIFICATION forming part of Letters Patent No. 721,499, dated February 24:, 1903. Application filed May 16, 1902. Serial No. 107.676. (No model.)

To all whom it may concern.-

Be it known that I, LOUIS BRENNAN, a subject of the King of Great Britain and Ireland,

' tion of increased or diminished'mechanical force onpressure to a-portionnf my new c0m'-' poundreducing-valv In ordinary reducing-valves a valve is operated by a piston or diaphragm resisted by a spring or weight. The valve is Opened to the source of superior fluid-pressure by the spring or weight and is closed by the fluidpressure admitted to the piston ordiaphragm, the pressure in the chamber thus being kept.

constant at that intensity which is necessary to move the piston or diaphragm against the spring. proportion to the area of the piston or diaphragm, then the constant pressure is high. If it be small, then the constant pressure is low. If the pressure on the spring be increased, the reduced pressurecin the chamher will increase but if the pressure be reduced the pressure in the chamber will not fall till the fluid has been discharged by feeding the apparatus which it is supplying.

My invention consists in a combination of reducing and discharging valvQiWhiQh en- .'--e. l emb at a e y pfessure, which rises and falls as themecham ables meanest ical force applied to the valves increases or diminishes.

In the accompanying drawings, in which similar letters denote similar parts, Figure 1 is a sectional elevation of one form of .my'invention. Fig. 2"is a sectional plan on the line A B, Fig. 1.- Fig. 3is a side elevation of Fig.

1. Fig. 4 is a sectional elevation of another form of my invention. Fig. 5 is a sectional plan on the line C D, Fig. 4. Fig. 6 is a side elevation of Fig. 4.

In carrying my invention into effect according to the form illustrated in Figs. 1 to 3 I construct a valve-casing a, inside which are If the spring resistance be great in annular channel fand g, respectively, leading in the case of valve cl to a pipe h, Fig. 2, com

municating with the fluid-supply reservoir,

and in the case-of valve 6 to a pipe in, Fig. 2, communicating with the atmosphere or an exhaust-chamber. Admission-valved,which may be held on its seat by a light spring,

such as- Z, is the reducing-valve, and it opens into a passage m, from which a pipe n leads to the chamber to be supplied with the com-' pressed fluid. Discharge-valve e opens from this passage'm and allows the fluid to be discharged from the chamber through pipe is into the exhaust-chamber or the atmosphere. The two pistons 12 and 0 project from the casing and maybe operated by means of pressure applied by the hand or otherwise directly or indirectly to the rod 0, which acts on the central pivot 10 of-an equal-ended lever (1. Whatever pressure be applied to the rod 0 is thus divided practically equally (the resistance of the light spring Z being negligible) between the two pistonsthat is,

both pistons are equally pressed, d, the reducing-valve, away from its seat, and e, the discharge-valve, onto its seat. this arrangement is to hold the reducingvalve open with exactly the same force as the discharge-valve is held closed. The reducing-valve d is forced onto its seat as soon as the pressure in the chamber supplied and the passage on rises to very slightly exceed the pressure with which the rod is thrust down. If the pressure on the central rod is lessened, the pressure on the dischargevalve will also be lessened and the fluidcontents of the chamber at once discharge till the pressure equals that closing, the valve. In

this manner an increase of mechanical pressure on the central rod ocauses pressure to rise (within the limits of the source of highpressure supply) and a diminution. of pressure causes the fluid-pressure to fall. The rod 0 moves vertically and is provided with The effect of sure fluid. A valve-seat is formed at one end of the casing a, and a valve 01' to fit it is formed on the cylindrical piston r. This valve may be held on its seat by a light spring Z. The valve opens into passage m, from which fluid at a regulated pressure is supplied to the receiving-chamber through the pipe or. The other end of the cylindrical casin g contains a lift-valve e, which is pressed upon a seat formed on the end of the hollow piston 7' when pressure is applied to the rod 0. This valve opens into the discharge pipe or chamber 7;. This construction of valve performs all the functions of the double valve hereinbefore described. Assuming that pressure is applied to the exhaust-valve by means of a rod 0' passing through a gland in the end of the casing,this pressure forces the exhaustvalve 6' onto its seat on the end of the hollow piston r, and if the pressure he suflicent the hollow piston will be thrust inward and the valve d at the other end be moved 05 its seat against the pressure of the spring Z plus Whatever pressure may be in the receiving-chamber. The fluid under pressure then flows from the supply-pipe h and is fed to the receiving-chamber at a regulated pressure. When the pressure in the chamber begins to exceed the I mechanical force or pressure applied to the discharge-valve, the valve d closes, thrusting the hollow piston along and at the same time moving the exhaust-valve 6 with it. So far the action is that of an ordinary reducing-valve. If, however, the pressure upon the discharge-valve be further reduced, the fluid contents from the receiving-chamber will flow through the hollow piston r, entering by way of holes 8, lift the discharge-valve e, and escape to the exhaust-chamber or the atmosphere until the pressure in the receiving-chamber just balances the pressure applied to the dischargevalve by the rod 0. In this manner the pressure within the receiving-chamber rises or falls with the force applied to the spindle 0, which controls both the discharge and piston valves. In this form I am also enabled to maintain a chamber ata varying pressure, rising and falling as the force acting on the valve increases or diminishes.

The invention may be applied to chambers used for containing fluid under pressure of varying intensity and is applicable to many purposes, such as pneumatic brakes, fluid steering-gear, and stair-tractors.

Having now described my invention, what I claim as new, and desire to secure by Letters Patent, is-

1. In combination in a fluid-pressure system, a casing, an admission-valve, a discharge-valve, a connecting-passage between the valves and means for applying a variable pressure to the valves, said means acting simultaneously and with equal force on the valves to open the admission-valve and close the discharge valve, substantially as described.

2. In combination in a fluid-pressure system, an admission-valve, a discharge-valve and means for applying a variable pressure to said valves simultaneously and respectively in opposite directions in relation to their seats.

3. In combination with a fluid-pressure sys tem a valve-casing containing an admission and a discharging valve which open in opposite directions, a rod operating both these valves, a passage situatedin the path of the fluid between these two valves leading to a receiving-chamber and a spring holding the admission-valve on its'seat, substantially as described.

In witness whereof Ihave hereunto set my hand in presence of two witnesses.

LOUIS BRENNAN. Witnesses:

ALBERT E. BARKER, FRANCIS J. BIGNELL. 

